[MERGE] Show a traceback when VFS operations are started on a smart server hosted repository.

[Andrew Bennetts]

Robert Collins wrote:
[...]
> === modified file 'bzrlib/remote.py'
> --- bzrlib/remote.py	2009-04-28 06:53:29 +0000
> +++ bzrlib/remote.py	2009-05-10 23:45:33 +0000
> @@ -688,6 +688,10 @@
>          invocation. If in doubt chat to the bzr network team.
>          """
>          if self._real_repository is None:
> +            if 'hpss' in debug.debug_flags:
> +                import traceback
> +                warning('VFS Repository access triggered\n%s',
> +                    ''.join(traceback.format_stack()))

Looks reasonable.  If it becomes too annoying perhaps we should mutter
rather than spam the terminal, but hopefully it'll just be an incentive to
fix the causes faster :)

I wonder if it would be a good idea to do this for RemoteBzrDir and
RemoteBranch too, but potentially spamming 3 back traces might be a bit
much...

bb:approve

-Andrew.